This R'Line Quadriceps machine is soft and comfortable while offering air resistance for those who want a smooth workout. It is based on air compression loading rather than machines based on iron-based weight stacks, so the residual inertia that comes from any movement does not occur. Push buttons at the hand or foot level allow you to adjust the load while you are exercising and the machine is quiet while being used and adjustments are simple and accurate. It features a welded frame that's 3mm thick, and a pneumatic jack directly drives the load. The range of motion adjustment pins and seat are chromed, and the equipment dimensions measure 1.45 x 0.80 x 1.20 m. The machine needs a compressor to operate.